Improved former for spiral springs



PATENT OFFICE.

VINCENT D. LENT, 0E CHELSEA, MASSACHUSETTS.

IMPROVEDFORMER FOR SPIRAL SPRINGS.

Specification forming part of Letters Patent No. 14,566, dated April 1, 1856.

To all whom it may concern:

Be it known that I, VINCENT D. LENT, of Chelsea, in the county of Suffolk and State of Massachusetts,have invented an Improvement in Formers for Making Conical Spiral Springs for the Use of Upholsterers and Others, of which the following is a full, clear, and exact description, taken in connection with the drawings forming part of this specification andthe letters of reference thereon marked.

Figure l is an elevation of the former in common use. Fig. 2 is an elevation of my improved former. Figs. 3 and 4 are partial plans of the common and improved formers, respectively. Figs. 5 and 6 are plans of springs made on the; common and improved formers, respectively.

The nature of my invention consists in So constructing the formeren which such springs are made that a part of their first and last convolutions Shall increase spirally or otherwise in size while revolving in a plane at right angles to the axis of the former, so that no part of these convolutions of the springs Shall be so nearly in the same vertical line with the next convolution as to cause contact when the Spring is compressed, and consequent irregularity of action, noise, and wear. That such contact is consequent upon the compression of a spring as it is made on a common former is obvious from the fact that that portion of the first and last convolutions which is in a plane at right angles to the axis of the spring must be so nearly coincident toa portion of the neit convolution that contact between them must be consequent upon its compression. To obviate this difficulty it is custernary to bend the springs made on the former in common use by hand, involving an amount of time and labor proportionate to the size of the springs, which is wholly saved by the use of my improved former.

To enable others skilled in the art to make and use my invention, I will to describe its construction and operation.

The former commonly used is truly represented by Fig 1, and is made of two frusta of cones placed with their small ends together, and on a square shaft passing through their centers. A groove is cut on these frusta at right angles to their axes for a portion of one convolution,and then at an angle to their axes around the frusta, terminating with a part of a convolution similiar to that rst described. 'Ihe groove serves to guide the wire While it is being formed into a spring. The arbor A is mounted on a frame which has Suitable bearings made to receive it, and the former is so fitted on the arbor as to be easily removed therefrom.

My improvement on the described former is made by adding to it two inclined planes, one of which is wound around each base of the frusta, and on which is cut a continuance of the groove for the guidance of the wire at similar angles to the axes of the frusta to those already described.

To form a spring, place the end of the wire under the catch B, revolve the arbor A, guiding the wire in the groove until the length of the spring -is completed, then cut the wire, withdraw the frusta C and' remove the spring, replace the frusta C, and the'operation may be repeated.

I am aware that springs might be made onrk conic frusta of such an angle that the parts of the Spring wound at right angles to the axis of such a former would not coincide so nearly with other parts of the spring that contact between them would follow compression. Springs made upon such a former, however, would have an unnecessary amount of niaterial,and I do not claim a former so constructed.

What I do claim, and wish to secure by Letters Patent, is-

A former constructed with suddenlyexpanded ends, as herein set forth.

, VINCENT D. LENT. Witnesses:

J. B. CROSBY, S. F. HAY. 

